AnsweredAssumed Answered

Queries regarding i.MX25 SLCDC

Question asked by ajithpv on Mar 9, 2012
Latest reply on Feb 3, 2015 by ajithpv

Hello Everyone,

We are using 128x64 dot matrix monochrome LCD in iMX25.
We have the below queries regarding i.MX25 SLCDC (Smart Liquid Crystal Display Controller).

1) As per the i.MX25 reference manual (IMX25RM.pdf) (chapter, The AUTOMODE [1:0] =00 defines how the command can be transferred through SLCDC. But it mentions that, the transmission is defined according to the DATABASEADR [16:0] bits of DATA BASE ADDRESS register and DATABUFSIZE [16:0] bits of DATA BUFFER SIZE register.
The data buffer address is 32 bit. Above it mentions DATABASEADR [16:0], so does it ignore the higher order bits of the address.
Wouldn't it be accessing wrong locations? Please provide an example.


2)In 41.2.6, Memory Map, SLCD base address starts from 0x1002_2000 (DATABASEADR),
    but in 2.1 system memory map, SLCDC base address is 0x53FC_0000. Is it type error?

3) AUTOMODE [1:0] =10, => command and data buffer used, command is sent automatically. Transaction started by writing DATA BUFFER SIZE register
 AUTOMODE [1:0] =00, => command buffer not used, only data buffer used. Commands are written to data buffer for sending commands

Question:  for sending data, again the buffer has to be updated and mode 01 needs to be used?

AUTOMODE [1:0] =01, command buffer not used, only data buffer used.

Question: used for sending data only?

4) We tested for sending the command using the AUTOMODE [1:0] =00, where RS should be low when sending data, but we are observing as shown in the snapshots (We probed D4). i.e., when RS is high, then some command is transferred, when low no data.
We have filled 0xA7 in buffer, DATA BUFFER SIZE set to 1. But we are getting continuous data as shown in snapshots.

 We tested with the Direct Register access method ( too, but we got the same signal as that of AUTOMODE [1:0] =00.


Any help would be very appreciated...

Thanks in advance